AUDITMEMO_080624 1

T E C H N I C A L M E M O R A N D U M



# Meteorological and PM 10 

# Monitoring Performance Audits at Winkelman, AZ and Hayden, AZ Air Quality Monitoring Stations (ASARCO LLC Hayden Plant Site), June 24, 2008

PREPARED FOR: John Hillenbrand/U.S. EPA

PREPARED BY: Josephine Le e/CH2M HILL

COPIES: Kevin Murdock/CH2M HILL

DATE: June 24, 2008

On June 24, 2008 , CH2M HILL conducted performance audit s on two air quality monitoring

stations located at the Winkelman High School in Winkelman, AZ and the Hayden

Maintenance Center in H ayden, AZ. This audit report details the results for the equipment audited. Performance audits were conducted on the following instruments:

Wind Speed (mph)

- 3 meters Wind Direction (degrees)

- 3 meters Ambient Temperature (degrees C) Barometric Pressure (mm H g)

Flow R ate ( SLPM )



### CH2M HILL Monitoring Station Performance Audit

An independent performance audit was performed by CH2M HILL Air Quality staff according to guidance outlined in EPA/600/R

- 94/038d, Quality Assurance Handbook for Air

Pollution Measurement Systems, April 1994. The system including individual measurements

must be within 7 percent of the calibrated instrument measurement. The pass/fail criteria

for audit results are based on these accuracies.

D uring each audit, all sensors, cups, vanes, shie lds, and cables are inspected to determine whether any unusual wear has occurred. In addition, systems and procedures are reviewed to determine if the station is being operated according to standard operating procedures and with sufficient quality assuranc e and control measures.

The audit was performed using calibration and test instrumentation for onsite sensor evaluation including: instruments for determining bearing condition, wind vane orientation, wind speed accuracy, wind direction accuracy and linear ity, ambient temperature and pressure, and flow rate.METEOROLOGICAL AND P M10 MONITORING PERFO RMANCE AUDITS AT WIN KELMAN, AZ AND HAYD EN, AZ AIR QUALITY M ONITORING STATIONS ( ASARCO LLC HAYDEN PLANT SITE), JUNE 24, 2008

AUDITMEMO_080624 2 

### Audit Results

Site 1

– Winkelman High School

PM 10 Monitor

– Thermo Fisher R&P Partisol (S/N 2025B218520601)

At ambient temperature and pressure, the instrument’s internal sensors were compared to NIS T traceable standards. Temperature was also verified using an ice bath and comparing the sensor reading to the NIST traceable standard. Results for temperature and pressure were within tolerances

as shown in Table 1.

A NIST traceable calibrated flow mete r was attached to the inlet of the PM 10 monitor. The instrument’s flow rate was compared to the standard flow rate. Results were well within tolerances as

shown in Table 1.

Table 1

PM 10 Instrument Test Ambient Temperature ( 0 C) Zero

Temperature ( 0 C) Pr essure

(mm Hg) Flow

(slpm)

Standard Response 40.2 3.8 703 16.62

Instrument Response 40.2 3.9 702 16.68

% Difference 0.0 2.6

- 0.1 0.4

Wind Speed

– 3 meters (RM Young 05103, S/N 69483)

A synchronous motor was attached to the wind speed sen sor that simulates wind speeds using known rpm rotational speeds. The zero response of the sensor was also checked by recording the datalogger value with the sensor not spinning (zero RPM). These values are also recorded. The results of this test

are shown in Table 2.

Table 2

Wind Speed Motor Test 0 rpm 300 rpm 600 rpm 900 rpm

Actual Desired Response (m/sec) 0 1.47 2.94 4.41

Wind Speed Sensor Response (m/sec) 0 1.44 3.00 4.44

Difference (m/sec) 0

- 0.03 0.06 0.03

Wind speed sensor bearing starting thr eshold was measured using a torque watch. The measured torque was <0.1 gm

- cm
, which corresponds to a starting threshold of <2.2 mph and indicated acceptable condition. The sensor and cups were inspected and found to be in fair condition. The bearings sound ed worn and it is suggested that they be replaced in the near future. The sensor passed

all audit tests.METEOROLOGICAL AND P M10 MONITORING PERFO RMANCE AUDITS AT WIN KELMAN, AZ AND HAYDE N, AZ AIR QUALITY MO NITORING STATIONS (A SARCO LLC HAYDEN PLANT SITE), JUNE 24, 2008

AUDITMEMO_080624 3 Wind Direction

– 3 meters (RM Young 05103, S/N 69483)

The sensor and vane were inspected and found to be in good condition. Linearity of the wind

direct ion sensor response was measured by rotating the directional vane in 90 degree increments and recording the sensor response. The sensor responded within 5 degrees of the desired direction and passed the audit. The cross

- arm alignment was checked using a p ortable transit. Setting the transit to the correct declination of 9.5 degrees, it was found that the cross

- arm was oriented to 180 degrees.



### Site 2

– Hayden Maintenance Center

PM 10 Monitor

– Thermo Fisher R&P Partisol (S/N 2025B218490601)

At ambient temper ature and pressure, the instrument’s internal sensors were compared to NIST traceable standards. Temperature was also verified using an ice bath and comparing the sensor reading to the NIST traceable standard. Results for temperature and pressure were wi thin tolerances

as shown in Table 1.

A NIST traceable calibrated flow meter was attached to the inlet of the PM 10 monitor. The instrument initially failed the leak test. The o

- rings were cleaned and the filter replaced and the instrument passed the leak c heck. The instrument’s flow rate was compared to the standard flow rate. Results are

within tolerances as shown in Table 3.

Table 3

PM 10 Instrument Test Ambient Temperature ( 0 C) Zero

Temperature ( 0 C) Pressure

(mm Hg) Flow

(slpm)

Standard Re sponse 41.6 1.5 701 16.74

Instrument Response 41.6 1.6 701 16.71

% Difference 0.0 6.7 0.0

- 0.2

Wind Speed

– 3 meters (RM Young 05103, S/N 69483 )

A synchronous motor was attached to the wind speed sensor that simulates wind speeds using known

rpm rota tional speeds. The zero response of the sensor was also checked by recording the datalogger value with the sensor not spinning (zero RPM). These values are also recorded. The results of this test

are shown in Table 4.

Table 4

Wind Speed Motor Test 0 rpm 300 rpm 600 rpm 900 rpm

Actual Desired Response (m/sec) 0 1.47 2.94 4.41

Wind Speed Sensor Response (m/sec) 0 1.56 2.97 4.5 0

Difference (m/sec) 0 0.09 0.03 0.09METEORO LOGICAL AND PM10 MON ITORING PERFORMANCE AUDITS AT WINKELMAN, AZ AND HAYDEN, AZ A IR QUALITY MONITORIN G STATIONS (ASARCO L LC

HAYDEN PLANT SITE ), JUNE 24, 2008

AUDITMEMO_080624 4 Wind speed sensor bearing starting threshold was measured using a torque watch. The measur ed torque was <0.1 gm

- cm
, which corresponds to a starting threshold of <2.2 mph and indicated acceptable condition. The sensor and cups were inspected and found to be in good condition. The sensor therefore passed all audit tests.

Wind Direction

– 3 meters (RM Young 05103, S/N 69483)

The sensor and vane were inspected and found to be in good condition. Linearity of the wind direction sensor response was measured by rotating the directional vane in 90 degree increments and recording the sensor response. The s ensor responded within 5 degrees of the desired direction and passed the audit.



### Summary and Recommendations

Two air quality monitoring stations were audited on June 24, 2008. The audit at Station 1, Winkelman High School began at 1310 CDT and was comple ted at 1413 CDT. The audit at Station 2, Hayden Maintenance Center began at 1541 and was completed at 1645. The data collected during audit periods

should be invalidated from the final data set.

The auditor reviewed site operating procedures with the s ite operator regarding bi

- weekly visits and data downloading procedures. It is recommended that the operators continue to visit the sites every other week to perform routine quality assurance checks, confirm proper operation of the instruments, and

downlo ad data from the instruments during these visits.

Currently there is no procedure for calibration/certification of the flow meter used to perform bi

- weekly

checks. The audito r recommend s that the flow meter used to perform these checks be calibrated and certified by the manufacturer on an annual basis.

The Winkelman High School station meteorological tower is not stable. It was recommended last year that this tower be firmly anchored to avoid unbalancing of the meteorological sensors. The RM Young

met eorological box is not securely attached to the tower, and also requires stabilization (also noted in last year’s report). The stabilization of the tower and meteorological box should be addressed. The wind speed sensor at this location passed all audit c riteria

, but the bearings should be replaced to avoid possible

failure in the future.

Overall, t he data currently being collected by both air monitoring station s meet U.S. EPA guidelines and can be used for project decisions.